Abstract
Nano-crystalline particles of barium hexaferrite have been prepared by co-precipitation route using solution of iron and barium chlorides. Water and a mixture of water and diethylene glycol with volume ratio of 1:3 were used as solvents in the process and co-precipitated powders were calcined at various temperatures for 1 h. The XRD results of calcined samples showed that the formation of single phase barium hexaferrite occurs at 900oC for sample synthesized in aqueous solution with a Fe+3/Ba+2 molar ratio of 11 and its formation is resulted from the reaction between mainly crystalline phases, while this temperature decreased to 700oC for sample synthesized in diethylene glycol/water solution with a Fe+3/Ba+2 molar ratio of 12 and the formation of barium hexaferrite consists of reactions between amorphous phases with crystalline phases. Crystallites of single phase barium hexaferrite with mean size of 35 nm were observed in the TEM image of the sample synthesized in diethylene glycol/water solution after calcination at 700oC and in this system the single phase barium hexaferrite could not be formed by using of the Fe+3/Ba+2 molar ratio of 11.
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